However, I can see that the Q&A format, with its "a question must have an objective answer" type rules might not actually float the wisdom in a review to the surface of the lake - for example, it will not always be useful to think of a code review as having an 'accepted answer' (perhaps 'suggestion(s) adopted' might be an alternative concept).

I can also see these fora requiring review-oriented tools - for example, highlighting and commenting on online code file(s) by each reviewer.

Assuming these type of proposal get off the ground, will Stack Exchange adapt itself to the different style of interaction?

Frankly, I think these proposals are going to fizzle out in beta. Forget about Q&A principles, every "review" site/forum I've ever seen has had exactly the same problem: Everybody wants reviews, but almost nobody wants to give them, and the ones who do eventually burn out. Maybe the community will somehow successfully map out a path around the myriad of incentive obstacles, but let's not ask this question prematurely.
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AarobotJan 17 '11 at 3:02